1. Field of the Invention
The present invention relates generally to a horticulture illumination system for use in growing plants and the like. In particular, the present invention provides an illumination system adapted with a plurality of vertically oriented light tubes so as to accommodate growing plants of different heights and having a cooling system integrated thereto.
2. Description of the Related Art
Horticulture growing systems are becoming an increasingly significant factor in the production of foodstuffs, flowers and decorative plants. Such growing systems generally include growing stations wherein plant roots are maintained in a sterile media. Nutrients, generally in water based solution, are provided to the roots, and radiation is supplied in to the plants from an illumination system with radiation in a range of wavelengths chosen to optimize plant growth. Illumination systems used within the horticulture industry vary widely in their basic design depending on such factors as the size and type of plants being produced and the general size of the growing facility. Most horticulture illumination systems employ a plurality of light sources, distributed in an array mounted at some distance over the plant's growing area. Overhead light sources tend to provide a cone of light directed downwards with the radiation intensity falling off from the center of the cone's circumference. Overhead lighting encompass each source of light to provide a generally uniform field of radiation that is vertically incident upon the underlying planar array of plants. Such systems are generally affixed to a structural ceiling and are cumbersome to relocate. Overhead lights require automated conveyors using chains and motors to relocate over different portions of a planting area in order to produce an even growing rate.
Another style of horticulture illumination systems employs a single point ground-level light source whose rays radiate in a full or partial arc with an intensity that decreases with distance above ground. Consequently, the amount of radiant energy available to a growing plant varies throughout the plant's height. A problem related to known ground-level illumination systems is a non-uniform light intensity incident upon plants as they increase in height during a full growing cycle.
Horticulture illumination systems typically do not employ cooling systems for individual light sources, but instead rely upon a universal cooling system to eliminate unwanted increases of temperature within the growing facility. These cooling systems tend to deposit dust or the like upon the exterior surfaces of the light source thereby decreasing the intensity of radiation transmitted to the growing plants.
U.S. Pat. No. 5,217,298 discloses a lighting system comprising a free-standing base supporting a track lighting strip in a substantially vertical position. Lighting elements may be positioned at any point along the track lighting strip. Spacer tubes and protective elements cover and enclose the track lighting strip.
U.S. Pat. No. 5,213,413 discloses an integral light and support to provides illumination in areas where temporary lighting is desirable and elongate members such as studs or joists are readily available. The light and support may be suspended from a flat wall having nails protruding from the surface through attachment to nail grooves provided. The integral light and support has a light housing that is pivotable and rotatable to direct the light in a variety of different areas without movement of the entire light and support.
U.S. Pat. No. 4,998,188 provides a wall-mounted lighting unit for creating a visual environment which is conductive to general care lighting and which requires both vertical lighting and brightness control. The lighting unit utilizes a prism design in a refractor which forms a portion of the bottom surface of the housing to provide horizontal illumination and internal linear optics for vertical illumination of the subject.
U.S. Pat. No. 4,796,169 provides for a lighting fixture is provided which includes a rotatable lamp and reflector system that can be adjusted to direct its maximum candlepower at a desired vertical angle. The lighting fixture also includes a rotatable glare shield that can be adjusted to vary the height of the top of the shield to change the degree of shielding provided.
From the discussion of the above art, it can be seen that there is a need for an improved horticulture illumination system for generating relatively uniform illumination as plants mature, and increase in height, that also overcomes or minimizes the above-mentioned problems associated with cooling requirements or structural rearranging.